Armrests for chairs, particularly office chairs, are known in the art. Early armrests were generally stationary, i.e., they were affixed to the chair in a position that was essentially non-moveable, either horizontally or vertically, in relation to the seated user. While chairs with such armrests are still common, it has been realized that, particularly in respect to office chairs, chairs with armrests capable of movement (either horizontally, vertically, or both) are more readily adaptable to a multitude of different users.
One example of an adjustable armrest is provided in U.S. Pat. No. 6,619,746 to Rosland, Jr. et al., which describes a height adjustable and rotatable chair arm for an office chair. The chair arm includes an arm assembly supported on a rotatable sleeve mounted on an upright support post, wherein rotation of the sleeve relative to the support post allows for rotation of the arm assembly. The sleeve further includes a vertical set of slots for receiving a portion of a lock mechanism located on the arm assembly. The sleeve can thus be moved vertically on the support post, the position maintained by the lock mechanism.
Similarly, U.S. Pat. No. 6,702,386 to Davis et al. describes a height and pivot-adjustable office chair arm assembly. The arm rest can be raised to different vertical positions by actuation of a gas cylinder surrounded by a shroud. The armrest is also capable of achieving multiple rotational positions by pivoting in a horizontal plane with a pivot support attached to the shroud.
While the ability to achieve multiple armrest positions is beneficial, it has recently been observed that with the increasing amount of time spent by a large number of people in performing office work, it is desirable, particularly for health maintenance, to provide office equipment, such as office chairs, that are ergonomically advanced. An example of the recognition of such need is U.S. Pat. No. 6,709,058 to Diffrient, which is hereby incorporated herein by reference in its entirety. The Diffrient patent describes an ergonomic chair that includes an adjustable armrest capable of being readily raised, or lowered, and optionally rotated in a horizontal plane.
While armrests capable of horizontal and vertical adjustment are known, there remains a need in the art for an ergonomic chair armrest capable of variable positioning by multiple users to provide the most ergonomically beneficial position possible. Further, there remains a need in the art for chairs incorporating such armrests.
Accordingly, the present invention provides an ergonomic chair armrest capable of vertical position adjustment, horizontal position adjustment, or both, allowing a variety of different users to achieve a most ergonomically desirable arm support.